Abraham Pineo Gesner ONB (May 2, 1797 – April 29, 1864) was a Nova Scotian and New Brunswickan physician and geologist who invented kerosene. Gesner was born in Cornwallis, Nova Scotia (now called Chipmans Corner) and lived much of his life in Saint John, New Brunswick. He died in Halifax, Nova Scotia. He was an influential figure in the development of the study of Canadian geology and natural history.

Abraham Pineo Gesner was born on May 2, 1797, at Chipmans Corner, Cornwallis Township, just north of Kentville, Nova Scotia. He was one of 12 children raised by Henry Gesner and Sarah Pineo, His father was a Loyalist, who emigrated to Nova Scotia after the American Revolution. Gesner was noted to be a great reader and a diligent student.

In his early twenties, Gesner began a venture selling horses to plantations in the Caribbean and the United States, but this enterprise failed after he lost most of his horses in two shipwrecks. Financially drained, Gesner returned to the family farm and married Harriet Webster, daughter of prominent Kentville doctor Isaac Webster in 1824. Reportedly, Webster offered to take care of Gesner's debts if he would study medicine and secure a steady income for his family. In 1825, Gesner travelled to London to study medicine at St Bartholomew's Hospital under Sir Astley Paston Cooper, and surgery at Guy's Hospital under John Abernethy. While primarily a medical student, Gesner developed an interest in the earth sciences and took lectures in mineralogy and geology. Gesner also established a lifelong relationship with Charles Lyell.

Gesner qualified as a doctor of medicine and settled in Parrsboro, Nova Scotia in 1827 as a travelling physician. Gesner also continued to pursue his passion for geology, reading the writings of notable geologists and developing a habit of picking up mineral specimens that caught his attention while making his rounds on horseback. In 1836, Gesner published his first book, Remarks on the Geology and Mineralogy of Nova Scotia. The book expanded on an earlier geological study by Charles T. Jackson and displayed Gesner's ability to express complicated concepts in simple language. Following the publication of Remarks on the Geology and Mineralogy of Nova Scotia, Gesner focused his efforts on studying geology and the sciences connected to it.

In 1838, the government of New Brunswick appointed Gesner as Provincial Geologist, and he moved to Saint John to conduct a geological survey of the province. For five years, Gesner spent his summers on geological fieldwork and his winters classifying specimens and writing reports. Although Gesner's geological studies were of high quality by the standards of the 1840s, he had no experience in mining and failed to make a realistic appraisal of the province's mineral reserves. Following the publication of Gesner's geological surveys, local entrepreneurs opened coal and iron mines in Queens County and were quickly disappointed by the extent and quality of the ore. Unhappy investors questioned the validity of Gesner's surveys and the provincial government terminated his employment in 1843.

During the first summer of his geological surveys, Gesner found a bituminous substance on the Petitcodiac River in Albert County, which he named albertite to differentiate it from coal or asphalt.

While in Saint John, Gesner amassed an extensive collection of minerals and wildlife specimens, which he assembled into a museum in 1842. Gesner's museum was one of its first of its kind in British North America and had 2173 items in its catalogue. The museum was a financial failure, and when Gesner left New Brunswick, the Saint John Mechanics’ Institute acquired the objects. In 1890, the Natural History Society of New Brunswick took over the collection, which is today a part of the New Brunswick Museum.

Following the termination of his geological appointment in 1843, Gesner returned to his family homestead at Cornwallis, Nova Scotia, in order to be with his father who was then 87 years old. While working on the family farm, Gesner also continued to practice medicine, write books, give public lectures and conduct experiments. He published notes for emigrants to New Brunswick, outlined the industrial resources of Nova Scotia, and built an electrical motor driven by a voltaic battery. In 1846, the government of Nova Scotia appointed Gesner Commissioner of Indian Affairs, and the following year he submitted a report on the living conditions of the Miꞌkmaq population. While visiting Mi'kmaq habitations across the province for his report, Gesner was known to donate his own money to assist impoverished families.